Posts from — June 2009

Dear Master Tech Automotive,

What is the difference between 10W30 motor oil and 5W30 motor oil?

Signed,

Confused

Michael Searcy says:

In 10W30 oil, for example, the two numbers (10 and 30) mean it’s a “multiviscosity’ or “multigrade” oil that’s effective over a range of temperature. The first number, 10, is an index that refers to how the oil flows at low temperatures. The second number, 30, refers to how it flows at high temperature. The W means the oil can be used in a winter.

A popular belief is that 5W30 oils were to thin to protect vital engine parts when they get hot and 10W30 caused harder starting on those cold winter morings, but numerous studies have concluded there is essentially no difference between  5W30 oils and their 10W30 brand mates. There is no visable way to tell the difference.

A larger number of automakers now recommend 5W30 as the “preferred” oil and even identify 5W30 on the oil filler cap. However, in most cases the manufacture also provided a chart with various temperature ranges and the acceptable viscosity. In our region the temperature ranges usually allow the use of either 10W30 or 5W30.  Most consumers in the state of Tennessee use the 10W30 because it is the most availabile and usually the least expensive, while maintaining quality and your manufacturer’s warranty.

The purpose of oil is to help protect the engine’s moving parts. But motor oil does much more than lubricate. It helps cool the engine, keeps it clean, prevents corrosion, and reduces friction to improve fuel economy. The worts mistake you can make is to put a single grade oil in an engine that was design to be run on a multigrade oil. Viscosity grade is important to the life of your engine, so be careful. Recommendations vary with the make, engine, and model year of the car, so check your owner’s manual and ask your mechanic for the proper grade of oil.

Instead of doing one big long vacation,I like to do several little mini-vacations spread throughout the year. Prior to going on vacation, I always get a little worried about my car making it all the way to where I’m going and back, so I like to have the guys at Master Tech take a look at my car before I go.

There’s an easy and inexpensive way to do this- just get a premium service oil change for the low, low price of $26.90 and mention to manager Jeff (or Klint if he’s running the desk in Jeff’s absence) that you’re heading out of town, you need a premium service oil change, and you just wanted to make sure everything was looking to be in good shape before you leave. The guys will check out your belts, hoses, tires, and other stuff for you, and you should be good to go.

Now, naturally if you’re having an actual problem you might need a pinpoint diagnosis to see what’s going on, but if your car is running fine and you just want to make sure everything looks OK, the premium service oil change is the way to go.

Incidentally, I just got back from Holiday World. If you’d like to read my thoughts on Holiday World, take a look right over here. Where are you going on vacation, Murfreesboro? Will you go somewhere, near or far, or are you just hanging out around the house?

I have a special affinity for Jeff, the manager, since his job was once my job and I know exactly what it’s like to be in his shoes. It’s a tough job some days, and other days it’s a complete blast. Jeff is far better at the job than I ever was- he has an amazing ability to remember people that I have never had, and he has a ton more patience than I ever had and ever will have. He’s just very well suited for the job.

So, you’d like to know more about Jeff? Here’s his profile:

Are you married or single? Do you have any kids?

I’ve been married for 17 years. 3 kids- a 14 year old son, an 11 year old daughter, and a 6 year old son.

Do you have any pets?

2 dogs- a mutt named Booboo and a puggle named Turner.

What are your hobbies?

Right now I’m restoring an old Ford truck with my son. I also love skeet shooting, golfing, camping, hiking, canoeing, and riding dirt bikes.

How long have you been working on cars?

Since I was 15.

Why did you go into the auto repair business?

I have an uncle that owned California Customs and I enjoyed watching and helping I then went through Ford Asset program and worked as an auto technician for several years, but the money would be good one week and bad the next which was a little hard to deal with, so I became a service writer and manager.

What’s your dream car?

1968 Shelby Cobra

What’s your favorite kind of car to work on?

So far, the best thing I’ve ever worked on was a 1971 Corvette convertible I helped my father-in-law restore.

What’s your least favorite kind of car to work on, and why?

Chryslers. Why? Well, they’re Chryslers.

Come on down and see the hardest working guy in auto repair today!